From 9f261464799bbbc4bf491e596db52014ab5a6984 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Standa=20Luke=C5=A1?= <exyi@outlook.cz>
Date: Sat, 11 Nov 2023 10:53:10 +0100
Subject: [PATCH] Fix error message in dotvvm.formatString date parsing

---
 .../Resources/Scripts/DotVVM.Globalize.ts     | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/Framework/Framework/Resources/Scripts/DotVVM.Globalize.ts b/src/Framework/Framework/Resources/Scripts/DotVVM.Globalize.ts
index 95928372c9..f1652270be 100644
--- a/src/Framework/Framework/Resources/Scripts/DotVVM.Globalize.ts
+++ b/src/Framework/Framework/Resources/Scripts/DotVVM.Globalize.ts
@@ -32,35 +32,34 @@ type GlobalizeFormattable = null | undefined | string | Date | number
 
 export function formatString(format: string | null | undefined, value: GlobalizeFormattable | KnockoutObservable<GlobalizeFormattable>, type: string | null) {
     value = ko.unwrap(value);
+    const originalValue = value;
     if (value == null || value === "") {
         return "";
     }
 
+    if (format === "") {
+        format = null
+    }
+
     if (typeof value === "string") {
 
         // DateTime, DateOnly or TimeOnly
         if (type === "dateonly") {
             value = serializationParseDateOnly(value);
-            if (format == null || format.length == 0) {
-                format = "D";
-            }
+            format ??= "D"
         } else if (type == "timeonly") {
             value = serializationParseTimeOnly(value);
-            if (format == null || format.length == 0) {
-                format = "T";
-            }
+            format ??= "T"
         } else {
             value = serializationParseDate(value);
         }
 
         if (value == null) {
-            throw new Error(`Could not parse ${value} as a date`);
+            throw new Error(`Could not parse ${originalValue} as a ${type || "date"}`);
         }
     }
 
-    if (format == null || format.length == 0) {
-        format = "G";
-    }
+    format ??= "G"
 
     return getGlobalize().format(value, format, getCulture());
 }